Wildfire Games has released 0 A.D. alpha 19 "Syllepsis" yesterday. This alpha release includes new gameplay features, graphics and user interface changes as well as various under the hood improvements.

0 A.D. is a historical war and economy game that runs on Linux, Windows and Mac OS X, which features several ancient civilizations, from Greece and Rome to Carthage and Persia.

The game comes with both singleplayer and multiplayer modes, and while there's no central server, players can use a lobby to discover other players and set up a game, or they can directly connect to each other using their IP addresses.

Changes in 0 A.D. alpha 19:

Gameplay:

non-siege units can now capture buildings and siege engines;

new victory modes: "Conquest Structures" (destroy or capture all enemy structures to win) and "Conquest Units" (destroy all enemy units to win);

ceasefire game mode: the game can be set so that all players are completely unable to attack their enemies for a predetermined time at the start of a game;

attack coordination: players can request allies (including bots) to attack a specific enemy by clicking a button next to the player name in the diplomacy window. Also, Petra AI now supports attack coordination;

Petra AI now warns its allies when it needs a tribute and lets them know when it advances to a new phase;

the Ptolemaic lighthouse now has its special feature implemented: it reveals the shore on the entire map;

increased maximum map height: the engine now supports an eight times greater range of terrain heights, allowing for the creation of maps with more diverse and impressive landscapes;

visual replay: re-run a game and understand what took place in real time;

aura visualization: units affected by an aura are now marked with an icon when the aura giver is selected;

new animals: new mastiff and wolfhound units have been added as well as a new rhinoceros;

the Roman units now have voices in Latin;

Other changes:

new pathfinder: The pathfinder is the component of the game engine that picks a route for a unit to move along from its current location to its target location, so that it does not collide with other units or with structures or with impassable terrain. The new pathfinder improves performance, but at the same time, it also introduces some new bugs;

XML validation: In 0 A.D., the behavior of units, buildings and other world objects is defined by their components, such as cost, health and more. All of these are described in XML files. The "grammar" of the XML files is now checked for correctness before being used by the game engine, which helps prevent technical problems;